<%@ page import="java.util.ArrayList" %>
<%@ page import="java.util.HashMap" %><%--
  Created by IntelliJ IDEA.
  User: xiaofeng
  Date: 2025/5/19
  Time: 19:41
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<%
    request.setAttribute("key1", null);
    request.setAttribute("key2", "");
    request.setAttribute("key3", new Object[]{});
    request.setAttribute("key4", new ArrayList<>());
    request.setAttribute("key5", new HashMap<>());

    request.setAttribute("score", 90);
%>
key1是否为空=${empty key1}<br/>
key2是否为空=${empty key2}<br/>
key3是否为空=${empty key3}<br/>
key4是否为空=${empty key4}<br/>
key5是否为空=${empty key5}<br/>

是否及格:${score >= 60 ? "及格": "不及格"}
</body>
</html>
